Luo Junfeng, Wang Xi, Pang Wenxing, Jiang Jing
College of Horticulture, Shenyang Agricultural University, Shenyang 110866, China.
Key Laboratory of Protected Horticulture of Education Ministry, Shenyang 110866, China.
Plants (Basel). 2024 Dec 21;13(24):3578. doi: 10.3390/plants13243578.
Plant height represents a pivotal agronomic trait for the genetic enhancement of crops. The plant cell wall, being a dynamic entity, is crucial in determining plant stature; however, the regulatory mechanisms underlying cell wall remodeling remain inadequately elucidated. This study demonstrates that the application of gibberellin 3 (GA3) enhances both plant height and cell wall remodeling in tomato () plants. RNA sequencing (RNA-seq) results of GA3 treatment showed that the DEGs were mostly enriched for cell wall-related pathways; specifically, GA3 treatment elicited the expression of the cell wall-associated gene (), whose overexpression resulted in increased plant height. Comparative analyses revealed that -overexpressing lines exhibited larger cell dimensions and increased XTH activity, along with higher contents of lignin, cellulose, and hemicellulose, thereby underscoring the gene's role in maintaining cell wall integrity. Conversely, treatments with ethephon (ETH) and 1-Naphthaleneacetic acid (NAA) led to suppressed plant height and reduced expression. Collectively, these findings illuminate a competitive interplay between GA and ethylene/auxin signaling pathways in regulating cell wall remodeling via SlXTH19 activation, ultimately influencing tomato plant height.
株高是作物遗传改良的一个关键农艺性状。植物细胞壁是一个动态实体，在决定植株高度方面至关重要；然而，细胞壁重塑的调控机制仍未得到充分阐明。本研究表明，赤霉素3（GA3）的应用可提高番茄植株的株高并促进细胞壁重塑。GA3处理的RNA测序（RNA-seq）结果显示，差异表达基因（DEGs）大多富集于细胞壁相关途径；具体而言，GA3处理诱导了细胞壁相关基因SlXTH19的表达，其过表达导致株高增加。比较分析表明，SlXTH19过表达株系表现出更大的细胞尺寸和更高的木葡聚糖内转糖基酶（XTH）活性，同时木质素、纤维素和半纤维素含量更高，从而突出了该基因在维持细胞壁完整性中的作用。相反，乙烯利（ETH）和1-萘乙酸（NAA）处理导致株高受到抑制且SlXTH19表达降低。总体而言，这些发现揭示了GA与乙烯/生长素信号通路之间在通过激活SlXTH19调控细胞壁重塑方面存在竞争性相互作用，最终影响番茄植株高度。
